Caching api

Good lullabot article on caching
http://www.lullabot.com/articles/beginners-guide-caching-data-drupal-7

API functions

• cache_set
  http://api.drupal.org/api/drupal/includes!cache.inc/function/cache_set/7
  Set the cache

• cache_get
  http://api.drupal.org/api/drupal/includes!cache.inc/function/cache_get/7
  Get the cache

• cache_clear_all
  http://api.drupal.org/api/drupal/includes%21cache.inc/function/cache_clear_all/7
  Clear the cache

Misc

• how to save data that is nid dependant
  One cache key by nid ?